The present invention relates in general to photoelectrolytic processes and is directed, more specifically, to the production of hydrogen and/or oxygen from water utilizing a photo-electrolytic process.
The concept of employing hydrogen as a fuel is attractive because it is abundant and nonpolluting. Unfortunately, although it is abundant it is not readily available in the molecular state and, in order for it to become a viable fuel satisfying significant future energy requirements, means for producing it in vast quantities in an economic manner will have to be identified and demonstrated.
Past technologies for the production of hydrogen, including the electrolysis of water or processing of fossil fuels, have typically required the expenditure of large amounts of energy usually from sources fueled by expendable materials.
In recent years some attention has been given to the production of hydrogen in closed-cycle, multistep, thermochemical processes for cracking water. However, the direct thermal decomposition of water requires temperatures in excess of 2500.degree. K. Furthermore, separation of the products, hydrogen and oxygen, is extremely difficult.
The direct photodecomposition of water requires radiation in the ultraviolet spectral region at wavelengths well below 2000 A. However, suitable intense ultraviolet light sources are not readily available nor are the materials which are readily transparent to such ultraviolet radiation.
What is really required is a practical means of producing hydrogen in a process that does not involve the unrealistic expenditure of our natural nonregenerable resources.